Patents by Inventor Kiwamu Tokuhisa

Kiwamu Tokuhisa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8268940
    Abstract: Disclosed is a halogen- and phosphorus-free flame-retardant adhesive resin composition which can be used in heat contact bonding of adherends at or below 250° C. and is excellent in heat resistance, solder heat resistance after moisture absorption, and processability. Also disclosed is an adhesive film produced from said composition. The flame-retardant adhesive resin composition comprises 65-98% by weight of a silicone unit-containing polyimide resin and 2-35% by weight of an epoxy resin having an acenaphthylene-substituted naphthalene skeleton. The adhesive film produced from the flame-retardant adhesive resin composition is suitable as an adhesive for a laminate for a multiplayer printed circuit board substrate, an adhesive for a hybrid circuit board substrate, and an adhesive for a coverlay film.
    Type: Grant
    Filed: March 6, 2008
    Date of Patent: September 18, 2012
    Assignee: Nippon Steel Chemical Co., Ltd.
    Inventors: Akira Mori, Kiwamu Tokuhisa, Kazuhiko Nakahara, Masashi Kaji
  • Patent number: 8026036
    Abstract: The present invention relates to a photosensitive resin composition excellent in pliability, ultraviolet sensitivity for development, developability with an aqueous alkali solution, and storage stability at room temperature and a circuit substrate employing the same. The photosensitive resin composition includes a siloxane-containing polyamic acid resin having structural units respectively represented by the following formulae (1), (2), and (3) and a photopolymerization initiator incorporated therein. The circuit substrate is coated with the photosensitive resin composition.
    Type: Grant
    Filed: March 24, 2006
    Date of Patent: September 27, 2011
    Assignee: Nippon Steel Chemical Co., Ltd.
    Inventors: Kiwamu Tokuhisa, Kentaro Hayashi, Hironobu Kawasato
  • Publication number: 20100063217
    Abstract: Disclosed is a halogen- and phosphorus-free flame-retardant adhesive resin composition which can be used in heat contact bonding of adherends at or below 250° C. and is excellent in heat resistance, solder heat resistance after moisture absorption, and processability. Also disclosed is an adhesive film produced from said composition. The flame-retardant adhesive resin composition comprises 65-98% by weight of a silicone unit-containing polyimide resin and 2-35% by weight of an epoxy resin having an acenaphthylene-substituted naphthalene skeleton. The adhesive film produced from the flame-retardant adhesive resin composition is suitable as an adhesive for a laminate for a multiplayer printed circuit board substrate, an adhesive for a hybrid circuit board substrate, and an adhesive for a coverlay film.
    Type: Application
    Filed: March 6, 2008
    Publication date: March 11, 2010
    Inventors: Akira Mori, Kiwamu Tokuhisa, Kazuhiko Nakahara, Masashi Kaji
  • Publication number: 20090202786
    Abstract: The present invention relates to a photosensitive resin composition excellent in pliability, ultraviolet sensitivity for development, developability with an aqueous alkali solution, and storage stability at room temperature and a circuit substrate employing the same. The photosensitive resin composition includes a siloxane-containing polyamic acid resin having structural units respectively represented by the following formulae (1), (2), and (3) and a photopolymerization initiator incorporated therein. The circuit substrate is coated with the photosensitive resin composition.
    Type: Application
    Filed: March 24, 2006
    Publication date: August 13, 2009
    Applicant: Nippon Steel Chemicals Co., Ltd
    Inventors: Kiwamu Tokuhisa, Kentaro Hayashi, Hironobu Kawasato
  • Patent number: 6984714
    Abstract: This invention relates to a siloxane-modified polyimide resin which shows excellent adhesiveness and can be bonded by thermocompression at high temperature even after subjection to thermal hysteresis in the manufacturing step for electronic parts. This polyimide resin is obtained from an aromatic tetracarboxylic acid dianhydride (A) and a diamine (B) comprising 30–95 mol % of a bis(4-aminophenoxy)alkane (B1) and 5–70 mol % of a siloxanediamine (B2) as essential components.
    Type: Grant
    Filed: April 23, 2003
    Date of Patent: January 10, 2006
    Assignee: Nippon Steel Chemical Co., Ltd.
    Inventors: Kiwamu Tokuhisa, Hongyuan Wang
  • Patent number: 6887580
    Abstract: An adhesive polyimide resin which comprises a siloxane polyimide resin obtained from (A) an aromatic tetracarboxylic dianhydride and (B) a diamine ingredient comprising (B1) a diamine having a phenolic hydroxyl group, carboxyl group, or vinyl group as a crosslinkable reactive group and (B2) a siloxanediamine and has a glass transition temperature of 50 to 250?C and a Young's modulus (storage modulus) at 250?C of 105 Pa or higher; and a laminate which comprises a substrate comprising a conductor layer and an insulating supporting layer having at least one polyimide resin layer and, disposed on a surface of the substrate, an adhesive layer comprising a layer of the adhesive polyimide resin. The adhesive polyimide resin and the laminate have satisfactory adhesion strength even after exposure to a high temperature of up to 270?C and further have excellent heat resistance in reflow ovens. They are hence suitable for use in the bonding of electronic parts.
    Type: Grant
    Filed: January 26, 2001
    Date of Patent: May 3, 2005
    Assignee: Nippon Steel Chemical Co., Ltd.
    Inventors: Kiwamu Tokuhisa, Akira Tokumitsu, Kazuaki Kaneko
  • Publication number: 20030212245
    Abstract: This invention relates to a siloxane-modified polyimide resin which shows excellent adhesiveness and can be bonded by thermocompression at high temperature even after subjection to thermal hysteresis in the manufacturing step for electronic parts. This polyimide resin is obtained from an aromatic tetracarboxylic acid dianhydride (A) and a diamine (B) comprising 30-95 mol % of a bis(4-aminophenoxy)alkane (B1) and 5-70 mol % of a siloxanediamine (B2) as essential components.
    Type: Application
    Filed: April 23, 2003
    Publication date: November 13, 2003
    Inventors: Kiwamu Tokuhisa, Hongyuan Wang
  • Publication number: 20030012882
    Abstract: An adhesive polyimide resin which comprises a siloxane polyimide resin obtained from (A) an aromatic tetracarboxylic dianhydride and (B) a diamine ingredient comprising (B1) a diamine having a phenolic hydroxyl group, carboxyl group, or vinyl group as a crosslinkable reactive group and (B2) a siloxanediamine and has a glass transition temperature of 50 to 250□C and a Young's modulus (storage modulus) at 250□C of 105 Pa or higher; and a laminate which comprises a substrate comprising a conductor layer and an insulating supporting layer having at least one polyimide resin layer and, disposed on a surface of the substrate, an adhesive layer comprising a layer of the adhesive polyimide resin. The adhesive polyimide resin and the laminate have satisfactory adhesion strength even after exposure to a high temperature of up to 270□C and further have excellent heat resistance in reflow ovens. They are hence suitable for use in the bonding of electronic parts.
    Type: Application
    Filed: July 30, 2002
    Publication date: January 16, 2003
    Inventors: Kiwamu Tokuhisa, Akira Tokumitsu, Kazuaki Kaneko
  • Patent number: 5916688
    Abstract: This invention relates to resin solution compositions for electronic materials consisting of organic solutions of 100 parts by weight of siloxanepolyimidepolyamic acid copolymers composed of imide segments formed by polycondensation of aromatic tetracarboxylic acid dianhydrides and siloxanediamines and amic acid segments formed by polyaddition of aromatic tetracarboxylic acid dianhydrides and aromatic diamines other than siloxanediamines and represented by the following general formula (1) (in which X is the residue of an aromatic tetracarboxylic acid dianhydride, Y is the residue of a siloxanediamine, Z is the residue of an aromatic diamine, l and m are integers independent of each other, and n is an integer of 1 or more) and 1 to 50 parts by weight of epoxy resins. The compositions are storage-stable and curable at relatively low temperature and yield cured products with an excellent balance of heat resistance, high-frequency characteristics, chemical resistance and stress relaxation characteristics.
    Type: Grant
    Filed: February 18, 1998
    Date of Patent: June 29, 1999
    Assignee: Nippon Steel Chemical Co., Ltd.
    Inventors: Kiwamu Tokuhisa, Akira Tokumitsu, Isamu Takarabe